Windows 10: PC constantly crashing/freezing

I built this computer a few months ago, without any prior experience in building computers. I know I have made mistakes while building it, but I can't pinpoint what the problem is. I do not have the time to completely rebuild my computer. My computer has always been crashing a lot, but recently it began to crash more often, and sometimes, it even freezes.

Below includes minidump and system information:

https://drive.google.com/drive/folders/1apvCh_AuIL3GOIal34m8pEQ0ObnX8x3D?usp=sharing

:)

 

all games crash!

I suggest you run rthdribl > http://www.daionet.gr.jp/~masa/archives/rthdribl_1_2.zip
Increase the window size step by step and watch your vga temps permanently.
What happens?
If it crashes, run at stock speeds as suggested before and retry.

P.S.: When your system locks, does the display signal turn off after a time?
Stuttering sound or no sound at all when freezing?
What X1800XT model do you own exactly?

 

all games crash!

ive watch my temps and both the cpu and gpu are within normal ranges. when it freezes it simply freezes the image and stops the sound. i must reboot to get back to windows.

 

Gta 4 crashing constantly

Sup everyone, i seem to be having a very annoying problem. I purchased gta 4 recently and i installed it and it runs quite well, my system is listed in my specs. The problem with the game, is that about +/- 5 minutes of playing, the screen gets funny coloured squares and my whole pc crashes. I have xp sp3 installed. I have tried numerous things like clocking my cpu back to stock but to no avail. My pc is not overheating, thats for sure, i dunno. My mate just told me that it might just be a bug, but it seems strange that i bug in the game would cause my whole pc to crash. Any suggestions?